BCL1, a murine model of prolymphocytic leukemia. II. Morphology and ultrastructure.

The transplantable murine B-cell leukemia, BCL1, was examined by light and electron microscopy. The results show that the BCL1 cell closely resembles the prolymphocyte of human prolymphocytic leukemia (PLL). The spleen of animals transplanted with BCL1 is diffusely infiltrated by BCL1-prolymphocytes. Splenectomized animals given transplants of BCL1 develop a lymphomalike disease with less leukemia and bone marrow involvement than the nonsplenectomized transplant recipients. Ultrastructural features of the BCL1 cell are identical in the splenectomized and nonsplenectomized animals.